In the Syrian town of Khan Sheikhun, site of an alleged chemical weapons attack, residents still mourning their dead on Friday welcomed US strikes as a way to pressure Damascus.

"God bless Trump," said Abu Ali, in his forties, hours after the US launched a barrage of cruise missiles at a Syrian government air base in the central Homs province.

"God willing, these strikes will be a clear warning to (President) Bashar al Assad, to tell him: Bashar, enough killing and injustice against these people," he said.

The attack ordered by President Donald Trump was the first direct US military action against Syria's government since the conflict began six years ago.

It came after a devastating suspected chemical weapons attack on Khan Sheikhun on Tuesday that killed at least 86 people, among them 30 children, and left hundreds suffering symptoms including convulsions, vomiting or foaming at the mouth.

On Friday, the neighbourhood hit in the attack remained empty, with survivors decamping to other parts of the rebel-held town in the northwestern province of Idlib.

A boy affected by what activists say was a gas attack on the town of Telminnes in Syria. Reuters

Across the town, there was little foot traffic or other movement, with relatives of those who perished still receiving condolences at halls.

Amidst the quiet and the sadness, residents said they welcomed the American attacks.

"We consider these strikes not only as a reaction, but a way to avenge the blood of the martyrs who fell here in Khan Sheikhun," said Haj Kassar, a merchant in his fifties.

"They're above us, threatening us again," he said, as warplanes circled overhead, carrying out at least one strike outside the town.

'An end to suffering'

"It doesn't deliver even a small part of the justice the martyrs deserve," added 37-year-old Abu Mohib, an army officer defector.

"But it does lift the morale of the families of the dead," he said.

Syria's conflict began in March 2011 with anti-government protests, but has since spiralled into a bitter and complex civil war that has drawn in international players and jihadist fighters.

Since last year, opposition forces have suffered a series of defeats, and many in rebel-held territory expressed hope that US strikes could reverse the situation.

"We hope that this will change the balance of power and deal the decisive blow to the Assad regime," said Ali al-Khaled, a resident of the area hit in the suspected chemical attack.

"We are grateful to the American airforce and for the American response to the massacre in Khan Sheikhun," he said.

If confirmed, Khan Sheikhun would be the second deadliest chemical attack in the Syrian war, after a 2013 attack believed to have killed hundreds of people in Eastern Ghouta near Damascus.

The Eastern Ghouta attack was blamed on Syria's government and prompted then-US president Barack Obama to threaten military action, though he ultimately held off after a deal for Damascus to turn over its chemical arsenal.

In the Eastern Ghouta town of Douma, residents welcomed the US attack on Friday, but urged more military action.

"We hope that any foreign intervention... would be an intervention to bring an end to the suffering of the Syrian people -- not just a single hit followed by more crimes and killing," said 30-year-old Abu Shahid.

'Not enough'

"There should be a bigger deterrent to killing people than this," added resident Abu Khalil. "I don't think this is enough."

And others expressed hope that Washington could ground all Syrian government planes.

"In reality, Syrians don't care about military strikes as much as they care about a no-fly zone for all aircraft," said 27-year-old Hassan Taqiddin.

"In the end, these strikes have very limited impact. They hit this airport, then what?"

More than 320,000 people have been killed and over half the country displaced since Syria's conflict began, shattering families.

"Part of the Syrian people has fled, part is buried underground, another part is out chasing humanitarian aid," said Abu Ali in Khan Sheikhun.

"We just want Trump and his administration to put an end to this farce."